Patent GB-330575-A (GB)
Title: Process for the manufacture of soluble cellulose esters of higher organic acids
IPC: C08B3/10
Filed: 1929-03-11
Abstract: 330,575. Ellis, G. B., (Soc. des Usines Chimiques Rh¶ne-Poulenc). March 11, 1929. Cellulose carboxylates; preparatory treatment of cellulose.-Soluble cellulose esters of carboxylic acids containing at least 8 carbon atoms in the molecule are prepared by treating cellulose or its near transformation products with the anhydrides of these acids in the presence of sulphonic acids derived from aliphatic hydrocarbons as catalysts. The reaction may be carried out in presence of diluents, of which carbon tetrachloride, chloroform, benzene, and toluene are given as examples. The cellulose, or its near transformation products such as hydrocellulose, oxycellulose, or hydrocellulose are preferably subjected to a preliminary treatment by any of the following methods :-(1) treatment with the melted acid to which may be added a portion or the whole of the catalyst and diluent, and also if desired a small quantity of acid anhydride: (2) treatment for several hours in a heated atmosphere of the vapours of the acid; (3) treatment with hydrochloric esters of polyhydric alcohols, and particularly glycerin dichlorhydrin; (4) treatment with halogenated organic acids, particularly chloracetic acids. Examples are given of the preparation of the following esters of cellulose, methane sulphonic acid being the catalyst used :-(1) lauric ester by the action of lauric anhydride in presence of carbon tetrachloride on cellulose pretreated with dichlor. hydrin; (2) palmitic ester by action of palmitic anhydride, in presence of carbon tetrachloride, on cotton pretreated with dichlorhydrin; (3) palmitic ester by action of palmitic anhydride in presence of carbon tetrachloride on cellulose pretreated with monochloracetic acid; (4) palmitic ester by action of palmitic anhydride in presence of toluene, on cellulose pretreated with monochloracetic acid: (5) stearic ester by action of stearic anhydride in presence of carbon tetrachloride on cellulose pretreated with monochloracetic acid; (6) phenyl-acetic ester by action of phenyl acetic anhydride in presence of chloroform on cotton pretreated with mono chloracetic acid; (7) palmitic ester by action of palmitic anhydride in presence of toluene on cellulose pretreated with monochloracetic acid; (8) stearic ester by action of stearic anhydride on cotton pretreated in the presence of toluene with a small quantity of stearic anhydride and methane sulphonic acid; (9) phenyl-acetic ester by action of phenyl-acetic anhydride in presence of chloroform on cotton pretreated with air laden with the vapour of phenyl-acetic acid. A further example is given of the preparation of palmitic ester by the action of palmitic anhydride on cellulose pretreated with monochloracetic acid, in the presence of carbon tetrachloride, ethane sulphonic acid being used as catalyst. The esters obtained may be used for the manufacture of films, plastic materials, celluloid substitutes and varnishes; and they may be hot moulded without the addition of solvents or plasticizers. Specifications 201,510, 283,181, 287,880 and 297,766 are referred to.